Where does “адьё” come from?

адьё (Russian) comes from French adieu, from Old French a Dieu vos comant.

адьё (Russian): adieu

Definitions

Step	Language	Word	Meaning
1	French	adieu	farewell, adieu; goodbye, see you soon; hello
2	Old French	a Dieu vos comant	—

адьё — Etymology, Origin & Word History | Etymology Explorer